Advancing Forensic Science: A New Buccal DNA Collector
By Kathy Dix

Although non-invasive methods of DNA gathering are a boon in terms of comfort, they carry the disadvantage of reduced efficiency. Some research companies, however, have focused their efforts on improving the efficiency while retaining the ease of collection.

Traditionally, the most common method of obtaining DNA is via blood, but the pain or mess associated with such a process demanded the development of a non-invasive method of collection. There are non-invasive techniques in existence, such as scraping buccal cells from the inside of the cheek. However, the cheek-scraping method is not fool-proof and can require a second collection 15 percent to 30 percent of the time.

The Bode Technology Group plans to launch a new technology on October 1 the company says will revolutionize the process of DNA gathering. Like cheek scraping, the buccal DNA collector is non-invasive; unlike cheek scraping, however, it is more accurate. With Bode's new method, a re-draw is required in less than 1 percent of cases.

Although the current cheek-swab is similar to Bode's method, there are key differences between the two, points out Todd Bille, assistant laboratory director at Bode. "From the analysis perspective, a traditional oral swab may not be uniformly saturated with saliva and, therefore, buccal cells," he says. "The analyst will not be able to differentiate the stained portion of the swab and the unstained portion. This can lead to samples having to be re-analyzed for various reasons."

Although with the Bode collector, the analyst will still not be able to see the stained portion, the manner of collection will inherently result in more consistency across the entire sample area.

Another issue with the traditional swab is that it is not protected while it dries in its packaging, and it may "bleed" onto or through the envelope. But in a busy emergency room or sexual assault examination room, medical staff members do not have the leisure to air-dry a swab before packaging it. If swabs were air-dried before being packaged, samples could be switched if multiple victims were being examined during the course of the day, Bille points out. The Bode technology, however, allows the sample to air-dry in its package while it is protected from cross-contamination.

Within the next several months, the method will be tested by police departments in New York and Michigan. "It is efficient, lending itself to faster processing and automation, thereby making it easier for the laboratory, and for victims," says Randy Nagy, Bode vice president of sales and marketing.

Speeding up the process for laboratories can lead to improved efficiency in other arenas as well. Criminal cases are sometimes deferred because existing methods of DNA processing delays the availability of data. "Not only are cases being postponed because they are not being processed quickly enough, cases are not being analyzed at all because the process takes so long," Bille confirms. "Obviously this is not just due to the processing of the victim's reference sample in the form of an oral swab, but each part of the process that can be made more efficient cuts down the time it takes to complete the entire analysis."

Needless to say, a faster technique would be a boon to laboratories -- and to the court system. "More and more forensic laboratories are moving toward a high-throughput method of processing sexual assault kits that are currently stockpiled in evidence vaults across the country," continues Bille. "Technology that is amenable to a high-throughput process is a necessity at the front end of the entire process. The front end in this case is the initial collection."

Although it is a new development, the Bode collector is comparable in cost to existing methods. "The current technology incorporates many benefits from many different devices and combines them into one collection method, utilizing existing technology that has already been proven," says Nagy. However, incorporating a collection method that allows for greater efficiency will allow for a cost reduction in the analysis, Bille notes.

Over the long term, the efficiency of DNA collection will be increased. Although there will be little difference in the level of discomfort related to DNA collection -- Bille suggests that discomfort had already been minimized with the development of the standard cheek-swab procedure -- the Bode collector "maintains the needed comfort and collects a quality sample." Sample quality, he notes, may have been sacrificed with the traditional swab in favor of comfort. The Bode product is designed to recoup some of that lost quality.

Because the technology of the processing has also been improved, forensic laboratories will be capable of processing more cases at a faster rate. This, Bille remarks, is where the real benefits of the Bode collector come into play. "Analyzing the sexual assault kits in greater numbers at a faster rate accomplishes two vital goals," he adds. "One: it will bring closure to victims faster. Second: through the use of CODIS, it may prevent future sexual assaults and other violent crimes from occurring." And reducing the number of victims, he says, is the greatest advantage he can imagine as a result of these improvements.

The Bode collector does have some limitations. Currently, it is only intended for select applications. "It cannot, for instance, be used to replace a vaginal/cervical swab," notes Bille. "However, it is not limited to buccal cell collection -- it can also be used to store bloodstains or other biological fluids."

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